Views: 4 Author: Site Editor Publish Time: 2024-01-15 Origin: Site
1. Industry background and current situation
The processing of masterbatch has strict requirements on compounding technology and equipment: Pigments, additives, and base resin ingredients must be absolutely and completely accurately measured, and then uniformly dispersed and mixed into the base resin through a compounding system such as a twin-screw extruder or internal mixer.
The concept of masterbatch refers to concentrating pigments or additives into a resin matrix. Masterbatch is generally a standard 3-5mm size particle, and there are also 1mm micro particles. According to the type of pigment, masterbatch is generally divided into white, black and colored. The production of masterbatch can adopt premixing, sub-addition or color matching process.
At present, in masterbatch production, most of the pigments, additives, and basic resin components are manually premixed, which requires manual feeding and measurement. This process has a low degree of automation, poor formula accuracy, and high environmental pollution. In recent years, loss-in-weight feeders have been used to add separate addition processes in the production of black and white masterbatch, improving the accuracy and stability of the formula while reducing environmental pollution.
2. Typical applications
-Color masterbatch
-Special pigment effect masterbatch, such as pearlescent masterbatch
-Carbon black masterbatch
-White masterbatch
-PET fiber masterbatch
3. Measurement and color matching
Color matching process
The color matching process is generally a high-end application. Different toners are fed separately using a loss-in-weight feeder and added to the extruder, where they are plasticized, mixed, and produced to produce the desired color product. The commonly used matrix resins in this process are PE, PP and PA, PET. Accurate loss-in-weight feeders ensure final product quality.
Typical raw material composition
Resin: particles, bulk density 0.5-0.7Kg/L; good fluidity
Toner: powder, bulk density 0.2-0.4Kg/L; poor fluidity
Additive: powder, bulk density 0.2-0.4Kg/L; general fluidity
Additives: Mixed granules and powders, bulk density 0.3-0.4Kg/L; general fluidity
Process characteristics
● Each raw material is fed separately and accurately measured, making the batching operation very simple and convenient.
● Just clean the toner feeder and refill section
● The site is relatively clean and easy to control
● It has certain advantages for production lines that require a certain frequency of color changes.
● The toner and other raw materials are not soaked in advance, so the dispersion requirements of the extruder are relatively high.
Commonly used equipment components
● Replenishment feeder
● Feeding valve
● Loss-in-weight feeder
●Collection bin
● Twin-screw extruder or continuous internal mixer
Pre-mixing process
In the premixing process, all toners, additives, and basic resin raw materials are mixed in the mixer in advance. It is then fed into a twin-screw extruder or internal mixer, usually using a volumetric feeder.
Process characteristics
● The dispersion of colored masterbatch requires a certain soaking time, and the requirements for downstream molding machines are relatively low.
● It is best to make a single product. The cleaning workload of the high-speed mixer is relatively large.
Commonly used equipment components
●High-speed mixer
● Feeding station
● Pellets conveying device
